Hydrocarbon-free, non-polymeric formulations and articles

ABSTRACT

Disclosed herein are compositions comprising blends of at least one triglyceride; at least one fatty acid; and at least one fatty acid derivative, whereby said compositions exhibit improved processing and flame/burn characteristics. The compositions may, optionally, further comprise fillers, extenders, modifiers, binders, flame and article colorants, and perfumes and are useful in the manufacture of, for example, fireplace logs, fire starter blocks, candles, and the like.

BACKGROUND OF THE INVENTION

1. Field of Invention

The present invention relates to moldable and extrudable compositionsthat are useful for producing articles, such as candles and artificialfirelogs. The compositions, which are flammable and combustible,comprise additives, e.g. oils, fats, and their derivatives, forimproving processing and burn characteristics.

2. Description of Related Art

Fatty triglycerides and fatty acids derived from them by hydrolysis andremoval of glycerin are known to be employed as fuels in candles, firestarter blocks, fireplace logs, and similar articles. They are mixedwith polymeric and/or hydrocarbon (waxy-type) fuels or formulated intocomposites with various forms of fiber or other solid species, usuallyflammable materials.

U.S. Pat. No. 3,297,419 discloses a synthetic fuel log produced from aflame-supporting material that is solid at room temperature. A filler orextender of a combustible type is combined with the flame-supportingmaterial. The flame-supporting material and the extender are combinedwith a binder to provide an elongate synthetic fuel log that is said toremain intact during burning.

U.S. Pat. No. 3,843,336 discloses a self supporting log having aboutseventy percent of its fuel value derived from petroleum derivativescontained therein. The log has an extruded thermoset resin skeletonhighly filled with particulate vegetable matter. The woody particles arepreferably initially impregnated with one or more petroleum derivatives,and subsequently added to an aqueous solution of a prepolymer resin mix.The mixture is then extruded with preferably a screw extruder having aheated die barrel to concentrate the thermoset resin at the outersurface of the extrusion, forming a continuous casing.

U.S. Pat. No. 4,040,796 discloses an artificial firelog comprised of aflammable body typically formed of a particulate wood and wax mixturepreferably with salts added for flame color. In a preferred embodiment,by a coextrusion process, a groove is formed along the outer surface ofthe body and extends substantially its entire length. The groove isfilled with gelled starter fuel. The log is preferably formed with atleast one substantially flattened side with the gelled fuel filledgroove located just above the flattened side whereby the log can besituated with its flattened side on the fireplace grate or andirons andthe gelled fuel filled groove located along the lower preferably front,face of the log thereby facilitating the log's fast lightingcharacteristics. The log is provided with an over-wrapper having aninner low or medium density polyethylene coating and which over-wrapperis heat sealed about the log. When lighting, the over-wrapper isinitially lit and this also ignites the gelled fuel. The heat andpressure from the hot expanding combustion gases then softens andruptures the over-wrapper and allows the flame to spread along thegelled fuel in the notch thereby fully enveloping the firelog in flame.

U.S. Pat. No. 4,049,680 discloses organic amide waxes having at leasttwo amide groups per molecule are prepared by reacting monocarboxylicacids preferably fatty acids with organic di- or poly-isocyanates.

U.S. Pat. No. 4,326,854 discloses a synthetic firelog made by bindingcellulosic particles with a combustible binder produced by theinteraction of a liquid combustible by-product or waste product and amodifier, the resulting material being such as to be carbonizable oncombustion to form a porous skeleton which maintains the shape of thelog during burning. The by-product may be molasses, various waste oilsor pitches, or sulfite lye and the modifier interacts physically orchemically therewith to form a plastic, thixotropic binder material. Thecellulosic material may be sawdust, paper, or any of a variety ofcellulosic residues from the processing of vegetable materials.

U.S. Pat. No. 4,333,738 discloses an improved synthetic fire log thatcontains wood fibers or sawdust, coal liquid, molasses and paraffin waxin appropriate quantities. Green sawdust is first heated to atemperature of from 250 to 300° F. to reduce the moisture contentthereof and provide relatively dry sawdust. To the dry sawdust is addeda quantity of coal liquid while the sawdust is at an elevatedtemperature of at least 200° F. Next, molasses is added to the sawdust,coal liquid combination while the combination is in a temperature rangeof from 115-150° F. Thereafter, paraffin wax in block form is addedwhile the foregoing mixture is at an elevated temperature at leastsufficient to melt the paraffin. Upon thorough incorporation of thematerials, the resulting mixture is poured into a mold and compressed toform a stable, solid, compacted mass after which the mass is removedfrom the mold thus forming a synthetic fire log.

U.S. Pat. No. 4,813,975 discloses a composition of matter, which issuitable for manufacturing candles by pressing/extruding, which is basedon stearic/palmitic acid and also comprises: 0.2-10% (w.w) of a crystalmodifier and optionally 0.5-15% (w.w) of another, as to carbon chainlength adjacent, natural fatty acid and/or such fatty acid derivative.Preferably the stearic/palmitic acid is a mixture of stearic acid andpalmitic acid in the weight range of 20-80:80-20. The crystal modifieris usually of the ester type and is derived from a polyol with 2-4hydroxyl groups and higher fatty acid and/or dimeric fatty acid.

U.S. Pat. No. 5,868,804 discloses artificial firelogs that provide anatural visual and audible sensation so that the artificial firelogshave both a soothing flickering flame and a crackling or popping soundnormally observed only with natural wood logs. The crackling additivecan be mustard seeds, sesame seeds and synthetic hollow spheres.

U.S. Pat. No. 6,017,373 discloses an artificial firelog that contains 2%to about 6% coriander seed added to create a crackling sound that mimicsthe sounds produced during the burning of natural logs. The randomcrackling sound continues for approximately the same time period asobserved with the burning of natural wood firelogs and has an amplitudeand frequency of crackling sound that mimics burning natural wood logs.

U.S. Pat. No. 6,086,644 discloses a scented candle that includes acandle manufacturing material, a fragrance provider, and at least one ofpolypropylene glycol and polypropylene glycol monoalkyl ether of aspecified general formula.

U.S. Pat. No. 6,136,054 discloses a synthetic firelog made by mixingspecially processed waxed-cardboard or other wax coated papers ofvarying proportions with a binder/fuel. The binder/fuel consists of apetroleum wax or a mixture of waxes, the nature and extent of which issuitably modified by in situ admixture with the paraffin wax alreadypresent in the waxed-cardboard. Sawdust or other wood fillers may alsobe added. Upon thorough incorporation of the materials, the resultingmixture is extruded, molded, compressed, or otherwise formed, such thatthe resulting mass is sufficiently solid to hold its shape at normalroom temperature.

U.S. Pat. No. 6,268,466 discloses a low molecular weight, tertiary amideterminated polyamide that may be blended with a liquid hydrocarbon toform a transparent composition having gel consistency. The tertiaryamide terminated polyamide may be prepared by reacting “x” equivalentsof dicarboxylic acid wherein at least 50% of those equivalents are frompolymerized fatty acid, “y” equivalents of diamine such as ethylenediamine, and “z” equivalents of a monofunctional reactant having asecondary amine group as the only reactive functionality. The gelcontains about 5-50% tertiary amide terminated polyamide, with theremainder preferably being pure hydrocarbon. The gels are said to beuseful in formulating personal care products and other articles whereinsome degree of gel-like or self-supporting consistency is desired.

U.S. Pat. No. 6,503,077 discloses a tertiary amide-terminated dimeracid-based polyamide that may be blended with a solvent to form a gel.The solvent may be flammable, and a wick may be added to the resultinggel so as to form a candle. Depending on the composition, the candle maybe formed into a free-standing pillar, or may be better suited to beingplaced in a container. The solvent may, for example, be mineral oil ortriglyceride. A solid coating may be placed around the candle, foradvantages including enhancement of the mechanical stability of thegelled body, and elimination of the tendency of a gel to have an oilyfeel and to accept noticeable fingerprints. The solvent which, incombination with the tertiary amine-terminated dimer acid-based polymerforms a gel, may be or include a fragrance material. The gelledcomposition may also include fatty acid and/or a compound containingone, two, or more ester groups. In one aspect, the article does notcontain a wick, and is intended to function as a fragrance-releasingproduct.

U.S. Pat. No. 6,521,002 discloses a clear transparent candle, which canbe scented, made of a composition comprising at least one polyamideresin; at least one aliphatic acid alkyl ester having 16 to 40 carbonatoms total in the acid and alcohol moieties thereof; at least oneunsaturated alcohol having 11 to 20 carbon atoms; at least one polyetherdiol ester; at least one drying agent selected from the group consistingof saturated alcohols having 14 to 22 carbon atoms, fatty acid amides,and fatty acid bis-amides in specified ranges of proportions, 0 to 3parts by weight of at least one emulsifier, 0 to 10 parts by weight ofat least one fragrance and 0 to 1 part by weight of at least onepreservative. The candle can stand alone or be in a container.

U.S. Pat. No. 6,544,303 discloses a composite scented candle that has ahigh load scented shell and a core candle with a similar or lesserfragrance load. The inside candle can be wax, paraffin, gel oil orpolyamide-based and can be scented or unscented. The outside shell canbe made of paraffin wax and a reinforcement having a melting point of atleast 70° C. and is scented at a level so that fragrance is continuouslyreleased without burning and is further activated by lighting the corecandle.

U.S. Pat. No. 6,602,306 discloses an artificial firelog comprising amixture of combustible materials and a combustible binder and furthercontaining particulate coke comprising about 1% to about 35% by weightof the firelog, the coke particles having a size less than about 4 mm,to create a realistic crackling sound that mimics the sounds producedduring the burning of natural logs. The particulate coke has a preferredmoisture content between about 2% and about 20% by weight. Theparticulate coke may be combined in predetermined ratios with otherestablished crackle additives including natural additives such ascoriander seed to extend the time period during which the burningartificial firelog crackles. Preferably, the particulate coke comprisesmetallurgical coke.

U.S. Pat. No. 6,706,942 discloses environmentally degradable molded orextruded articles comprising a polyhydroxyalkanoate C4C6 copolymercomposition having short annealing cycle times. Such short annealingcycle times are achieved by compositions having a percentage of C6 unitsof 2-8%.

U.S. Pat. No. 6,712,865 discloses a colored flame candle and themanufacture thereof. The colored flame candle comprises a candle bodyand a candle combustion wick, wherein the candle body comprises aprimary combustion agent, a higher fatty acid amide and a higher fattyacid triglyceride as the strength- and flexibility-modifier, acolor-forming agent and conventional adjuvant such perfumes andpigments.

U.S. Pat. No. 6,719,816 discloses an artificial firelog comprisingcombustible cellulosic material, a combustible wax binder and an amountof sodium bicarbonate effective to reduce emissions of particulatematter (PM) and carbon monoxide (CO). The sodium bicarbonate comprisesabout 1% to about 10% by weight of the artificial firelog. Besidessubstantially reducing PM and CO emissions during combustion of theartificial firelog, the undesirable odor associated with combustion ofthe wax binder is decreased and the firelog's total burn time isextended. Moreover, the sodium bicarbonate is said to increase the “pokeresistance” of the firelog making the log suitable for outdoor use and anatural appearing white ash develops during the course of combustion.

A number of polymeric materials can be used instead of or in addition towaxes primarily for candle manufacturing. They are polyamides (U.S. Pat.No. 6,544,303; PCT WO 2001095871 and PCT Int. Application WO2001095871), ester-terminated polyamides or tertiary-amide terminatedpolyamides (U.S. Pat. Nos. 6,268,466 and 6,503,077), in-situ polymerizedvegetable oils and unsaturated carboxylic acids or anhydrides (GermanPatent 19619396), polyhydroxy alcoholate copolymers (U.S. Pat. No.6,706,942), polyether diol ester (U.S. Pat. No. 6,521,002) and vinylacetate-ethylene copolymers (U.S. Pat. No. 6,712,865).

Several non-polymeric materials have been used as the main component ofthe formulation. They are ethyl carbamate (Chinese Patent ApplicationPublication 1043340A), polybasic acid esters (Chinese Patent ApplicationPublication 1073201A), trimethyl citrate, di-alkyl oxalate, mono-alkylsuccinate, paraformaldehyde, ethyl hydroxyformate, urothropine, andstearic acid (U.S. Pat. No. 6,712,865).

Fatty acids, amides, including bis-amides, esters, and calcium stearateare also known as lubricants for numerous plastic materials (primarilythermoplastics). Such lubricants are added at up to ten weight percentto the polymeric materials to ease their processing [See PlasticsAdditives Handbook, 5^(th) edition by Hans Zweifel, Haser Publishers,Munich, 2000].

The disclosures of the foregoing are incorporated herein by reference intheir entirety.

SUMMARY OF THE INVENTION

As noted above, fatty triglycerides and fatty acids derived from them byhydrolysis and removal of glycerin are known to be employed as fuels incandles, fire starter blocks, fire logs, and similar articles. They aremixed with polymeric and/or hydrocarbon (waxy-type) fuels or formulatedinto composites with various forms of fiber or other solid species,usually flammable materials.

Altering the fatty materials with the use of additives for meetingrequired processing characteristics (hardness, softening point, ease offorming the object in a standard process, strength of the objectimmediately upon production and at a later time, moldability, moldrelease, extrudability and the like) of the burnable product and/orchanging the nature of the way the combinations burn (flame height, timeof burning, flame brightness and color, the ability of the object tohold together while burning etc.) can result in unique and novelcompositions, the production of which is not obvious.

Additionally, various interactions among the additives and the fuels canresult in both desirable and undesirable effects. Therefore, alteringthe compositions to achieve all the desired characteristics, while atthe same time avoiding the use of both polymeric and traditionalhydrocarbons, is especially challenging.

In accordance with the present invention, natural fats or oils aretypically used as they occur, generally in a liquid or paste form atambient temperature. Fatty acids, derived from triglycerides byhydrolysis and removal of the glycerin can also be used as they occur.Some of the properties of each of these can be improved by modifying thefuel stock used. Hydrogenation can be used either on the triglyceridesor on the fatty acids to change their physical characteristics by makingthem harder and more crystalline in nature. The fats and fatty acids canalso be blended either in hardened or unhardened state to achieve thedesirable properties. Lastly, fats and oils of differing carbon chaindistributions can also be utilized in these formulations to produce aneven wider variety of properties. Such techniques are known in the art;however, none of these techniques, alone, is sufficient to meet all therequired and above-described desirable characteristics of the productsinvolved.

Artificial fire logs (hereinafter referred to as “fireplace logs”) arecomposites that contain cellulosic materials, such as sawdust, and abinder that is produced from certain waxes that may also optionallycontain combustible additives that impart processing, combustioncharacteristics, and flame appearance.

Hydrocarbon-free, non-polymeric formulations based on natural oils,fats, and their derivatives with or without cellulose-containingcomponents are not believed to have been reported as moldable and/orextrudable owing to their very low softening points and poor burningcharacteristics: short burn time and low flame.

According to the present invention, there are provided non-polymeric,hydrocarbon-free formulations that are based on triglyceride-fatty acidblends (both soft and hard), serving as fuels. The formulations aresuitable for manufacturing moldable and/or extrudable compositions anduseful articles, such as candles and cellulosic material-filledartificial fire logs or fire starter blocks. Improved processing andflame/burn characteristics are achieved by combining these blends withfatty acid derivatives, such as metal stearates and ethylene bisamides.

Thus, the present invention is directed to a moldable and/or extrudablecomposition that is suitable for manufacturing useful shaped articlesand is based on triglyceride-fatty acid blends that also comprise fattyacid derivatives to achieve improved processing and flame-burningcharacteristics.

More particularly, the present invention is directed to a compositioncomprising a blend of:

(A) at least one triglyceride;

(B) at least one fatty acid; and

(C) at least one fatty acid derivative.

In another aspect, the present invention is directed to an article ofmanufacture comprising a composition comprising a blend of:

(A) at least one triglyceride;

(B) at least one fatty acid; and

(C) at least one fatty acid derivative.

In still another aspect, the present invention is directed to a methodfor improving the processing and flame-burning characteristics ofarticles comprising a blend of at least one triglyceride and at leastone fatty acid, wherein the method comprises adding to said blend atleast one fatty acid derivative.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

As specified above, the present invention is directed to, inter alia, acomposition comprising a blend of:

(A) at least one triglyceride;

(B) at least one fatty acid; and

(C) at least one fatty acid derivative.

The fatty acid(s) of the blends of the present invention is (are)preferably of the formula R₁COOH, wherein R₁ is an aliphatic hydrocarbonradical of 5 to 25 carbon atoms, including, but are not limited to, suchacids as caprylic, oleic, capric, linoleic, lauric, linolenic, myristic,eicosenoic, palmitic, lauroleic, margaric, myristoleic, stearic,palmitoleic, arachidic, gadoleic, behenic, erucic, pelargonic,elaeostearic, isostearic, licanic, neodecanoic, arachidonic, 2-ethylhexanoic, lignoceric, caproic, pentadecanoic, hydroxystearic,phenylstearic, and the like. The acids employed can, if desired, behardened by hydrogenation where they are not saturated to begin with.Mixtures of such acids can, of course, be employed.

The triglyceride(s) of the blends of the present invention is (are) anester, or esters, of glycerol with one or more fatty acids that arepreferably of the formula R₁COOH, wherein R₁ is an aliphatic hydrocarbonradical of 5 to 25 carbon atoms, as described above.

The fatty acid derivative(s) of the blends of the present invention arepreferably selected from the group consisting of metal salts of fattyacids, fatty acid amides, fatty acid bisamides, and mixtures thereof.Preferably, the fatty acids from which the derivatives are preparedwill, again, be of the formula R₁COOH, wherein R₁ is an aliphatichydrocarbon radical of 5 to 25 carbon atoms, as described above.

The metallic moiety of the metal salts of the fatty acids is preferablyselected from the group consisting of alkali metals and alkaline earthmetals, for example, sodium, potassium, magnesium, calcium, and thelike. Sodium and calcium are preferred, calcium most preferred. Again,the fatty acid moiety is preferably of the formula R₁COOH, wherein R₁ isan aliphatic hydrocarbon radical of 5 to 25 carbon atoms, as describedabove. The fatty acid moiety most preferably comprises stearate and/ormixtures of stearate with other naturally occurring and commerciallyavailable fatty acids. Again, mixtures of such salts can be employed.

The bisamide waxes, ethylene bisstearamide and methylenebisphenylstearamide, are known and have a number of uses, for examplethey are used either alone or in admixture with other materials aslubricants for various applications including the compaction of metalpowders; the drawing of wire; the extrusion of plastic pipe; sand shellmolding; the processing of polystyrene; and as mould release anddetackifying agents for synthetic rubbers.

In addition, it is known that such bisamide waxes can be used asadditives for a number of materials including paper to improveresistance to water and oil; paraffin waxes and asphalts to increase themelting point thereof, adhesives to reduce viscosity and eliminate coldblock and tack. Such bisamide waxes have also been used as anti-staticagents for cellophane.

These bisamide waxes are commercially available and can be manufacturedby a process in which a fatty acid is reacted with a diamine at atemperature above the melting point of the resulting amide wax; thereaction proceeds with the evolution of water.

The most widely used bisamide wax is ethylene bisstearamide, which canbe made by reacting one mole of ethylenediamine with two moles ofstearic acid. Similarly, methylene bisphenylstearamide can be preparedby the reaction of stearic acid with methylenedianiline. Alternatively,these products can be made by the reaction of a fatty acid of theformula R₁COOH, wherein R₁ is and aliphatic hydrocarbon radical of 5 to25 carbon atoms, as described above, with an organic isocyanate, asdisclosed in U.S. Pat. No. 4,049,680.

For use in the practice of the present invention, ethylene bisamides arepreferred. Most preferred is N,N′-ethylene bis-stearamide (EBS).

Those skilled in the art will understand that the fatty acid amides thatcan be employed in the practice of the present invention can be preparedfrom such fatty acids and monoamines.

The total additive content, i.e., the content of the fatty acidderivative(s), (C), preferably is in the range of from about 3 to about99 percent by weight based on the total weight of (A), (B), and (C);more preferably, from about 5 to about 20 percent by weight; mostpreferably, from about 10 to about 15 percent by weight.

The preferred weight ratios between the triglycerides and the fattyacid-containing fuels in the blends of the present invention are in therange of 60/40 to 40/60 for most applications, although wider ranges,such as 90/10 to 10/90, may apply when specific properties, e.g., burntime and/or flame height, are weighted more heavily than others.

In addition to the fatty acids, triglycerides, and fatty acidderivatives of which the compositions and articles of the presentinvention are comprised, such compositions and articles may, if desired,further comprise additional fillers, extenders, modifiers, binders,flame and article colorants, perfumes, and the like. In particular,where such articles are fireplace logs or fire starter blocks, fillersthat are cellulose-containing materials will normally be included. Suchcellulose-containing materials can include, but are not limited to,cellulose fiber, cellulose derivatives, wood chips, wood fibers, woodflour, flax, kenaf, sisal, jute, rice hulls, cotton, hemp, and the like.

Suitable cellulose-containing fillers for use in the practice of thepresent invention may be derived from any of a number of availablesources, such as ground wood, sawdust, wood flour, ground newsprint,magazines, books, cardboard, wood pulps (mechanical, stone ground,chemical, mechanical-chemical, refined, bleached or unbleached, virginor recycled, sludge, waste fines), and various agricultural wastes (ricehulls, wheat, oat, barley and oat chaff, coconut shells, peanut shells,walnut shells, straw, corn husks, corn stalks, jute, hemp, bagasse,bamboo, flax, and kenaf).

Fibrous wood material, which is preferred because of its abundance andsuitability can be derived from either soft woods or evergreens or fromhard woods commonly known as broad leaf deciduous trees. While soft woodis the primary source of fiber for use in the practice of the presentinvention, additional fiber make-up can be derived from a number ofsecondary or fiber reclaim sources, including bamboo, rice, sugar cane,flex, kenaf and recycled fibers from newspapers, boxes, computerprintouts, and the like.

Where fillers are included in the compositions of the present invention,they are preferably present in the range from about 1 to about 60percent by weight, based on the weight of the total composition.

Various features and aspects of the present invention are illustratedfurther in the examples that follow. While these examples are presentedto show one skilled in the art how to operate within the scope of theinvention, they are not intended in any way to serve as a limitationupon the scope of the invention.

EXAMPLES Softening Point Improvement

An important characteristic of a fuel, whether or not combined with afibrous material, is the ability to hold together the formed article ina cohesive unit that doesn't melt and flow off or slump into an unusablepile. This property is dependent upon more than just the melting point.A test method, the Ring and Ball Test, was used to determine thesuitability of formulations in this regard.

The Ring and Ball Test measures strength as the melting point of thefuel is approached: a ¼ inch thick disc made up of the sample, e.g., acomposite, must support a steel ball ⅜ of an inch in diameter andweighing 3.5 to 3.6 grams. This is a variation of other ring and ballsoftening point tests, such as ASTM D 36, and uses the same equipment.The sample disc is ⅝ of an inch in diameter in the bottom 0.1 inch ofthickness, and ¾ of an inch in diameter in the top 0.15 inch ofthickness, thus resting on a lip in the sample holder. The steel ballsits on top of the sample disc, held roughly centered by a retainer withthree prongs that keep the ball from rolling. Two of the sample holders,sample discs, balls, and retainers are mounted in a framework andimmersed in water in a 1000 mL beaker, with the samples suspended aboutmidway up the beaker. The water is heated on a heating plate at a rateof about 5° F. (about 2.75° C.) per minute, with moderate stirring ofthe water by a 30 mm Teflon coated magnetic stirring bar. Thetemperature is read from a thermometer with its bulb suspended at aboutthe sample level, between the two samples. The temperature at which eachball falls through the sample disc is recorded, and the average value isused as the softening point of that composition.

Sample Preparation

Samples are prepared by weighing appropriate amounts of the fuel andadditives into a 250 mL beaker, then adding a 30 mm magnetic stirringbar. The beaker is then placed on a heater/stirrer, and a thermometer issuspended in the beaker so that its bulb does not touch the bottom. Theheater is then turned on to a level to produce a surface temperature inthe range of 300 to 350° F. (149 to 177° C.) and the stirrer turned onwhen enough of the sample is molten to allow mixing. The sample isheated and stirred until it is a clear solution—normally above 220° F.(104° C.).

For example, 97.0 grams of hard tallow (Iodine value below 5) wereweighed into a tared 250 mL beaker along with 3.0 grams of ethylenebisstearamide in prill form. Heating is started and by the time atemperature of about 170° F. (76° C.) is reached, there is enough meltedhard tallow to begin stirring. Heating and stirring are continued untila clear solution is achieved at about 270° F. (132° C.). In the case ofstearates, a slight haze may be left in the solution. Two sample holderswere placed on a clean ceramic surface, and the resulting compositionpoured carefully into them until they just ran over. The samples wereallowed to cool into solid discs and stabilized for at least three hoursat room temperature. They were then tested as described above.

Burn Time and Flame Height

1. Fire Log-Type Composites

In order to measure the effects of various additives on the burningcharacteristics of articles, such as burn time and flame height, samplesof fuels modified by the additives were mixed with wood chips on a 50/50basis (by weight) and formed by finger pressure into 1.5 inch diameterby a ¾ inch high conical piles. These comprised 5 grams of wood chipsand 5 grams of a fuel/additive blend, each on a 70 mm aluminum weighingcup, arranged in a matrix on a metal surface. Each was ignited with theuse of flame about a ¾ inch long from a Harbor Freight brand butanemicrotorch that was applied for one second. Flame characteristics wereobserved and recorded as shown in Table 3. Burn times were recorded inminutes until the flame went out. Flame heights were recorded incentimeters, measured as average heights during stabilized burn byplacing a ruler behind the sample and visually measuring the middle ofthe flickering height.

2. Candle Formulations

Burn time and flame height of the candle-type formulations and articleswere determined on samples cast into cylindrical discs in ring and ballsample holders with wicks suspended in their centers, with the wicks cutoff at a height of 0.5 inch above the porcelain surface. Samples wereallowed to harden, removed from the rings, and the wicks were ignited asdescribed above. Flame height was measured from candle top to middle ofthe flickering range, against a ruler as described above. Bum time wasrecorded in minutes until the flame went out.

The data presented in Table 1 demonstrate the unique ability of ethylenebisamides, especially N,N′-ethylene bis-stearamide (EBS), to increasesubstantially the ring and ball softening points of triglyceride fuels.Metal stearates, of which calcium stearate (CaSt) was the mostefficient, resulted in a less pronounced effect for tallow, hard tallow,and tallow fatty acids. In the case of soft tallow fatty acids, the EBSprovides the only effective treatment and even then the effect is small.CaSt was more efficient than EBS for improving the softening point ofhard tallow fatty acids, while sodium stearate showed no increase at allin either triglycerides or fatty acids.

TABLE 1 Effect of Additives on Softening Point of Individual Fuels inWood-containing Composites Additives Softening Concen- Point, Fuel typeAdditive tration, % ° F. Tallow (T) None 0 103 Tallow EBS 3 118 TallowEBS 5 198 Tallow EBS 7 205 Tallow CaSt 2 115 Tallow CaSt 4 118 HardTallow (HT) None 0 141 Hard Tallow EBS 3 143 Hard Tallow EBS 5 170 HardTallow EBS 7  212+ Hard Tallow CaSt 4 142 Hard Tallow NaSt 4 141 TallowFatty Acids (TFA) None 0 112 Tallow Fatty Acids EBS 3 118 Tallow FattyAcids EBS 5 126 Tallow Fatty Acids CaSt 4 114 Tallow Fatty Acids CaSt 6116 Hard Tallow Fatty Acids (HTFA) None 0 144 Hard Tallow Fatty AcidsEBS 7 148 Hard Tallow Fatty Acids CaSt 2 150 Hard Tallow Fatty AcidsCaSt 3 153 Hard Tallow Fatty Acids CaSt 4 161 Hard Tallow Fatty AcidsCaSt 5 164 Hard Tallow Fatty Acids CaSt 6 185 Hard Tallow Fatty AcidsNaSt 4 142

The results in Table 2 show an unexpected, synergistic effect of thefuel compositions [hard triglyceride (HT), soft triglyceride (T), hardtriglyceride fatty acid (HTFA), or soft triglyceride fatty acid (TFA)]and the presence of EBS and/or CaSt on increasing the softening point ofthe formulations.

TABLE 2 Effect of Additives on Softening Point of Combined Fuels inWood-containing Composites Softening Fuel 1,% Fuel 2, % Additive 1, %Additive 2, % Point, ° F. HT, 50 TFA, 50 0 0 128 HT, 47.5 TFA, 47.5 EBS,5 0 142 HT, 47.5 TFA, 47.5 CaSt, 5 0 144 HT, 45 TFA, 45 EBS, 5 CaSt, 5153 T, 50 HTFA, 50 0 0 135 T, 47.5 HTFA, 47.5 EBS, 5 0 156 T, 47.5 HTFA,47.5 CaSt, 5 0 172 T, 45 HTFA, 45 EBS, 5 CaSt, 5 176

The effect of calcium stearate, an increase in burn time with only aslight reduction in flame height in each set, was unexpected (see Table3). Both CaSt and EBS showed a tendency to reduce flame height onlyslightly for all fuel types. Tallow fatty acids burned the most quickly.All fatty acid-containing formulations burned with a higher flame thanthe triglycerides.

TABLE 3 Effect of Additives on Burn Time and Flame Height ofWood-containing Composites Flame Burn Addi- Concen Height, time, FuelType tive tration, % cm min. Tallow (T) None 0 7.5 9.0 Tallow EBS 5 6.310.0 Tallow CaSt 5 6.3 13.5 Hard Tallow (HT) None 0 7.5 11.0 Hard TallowEBS 5 6.3 11.0 Hard Tallow CaSt 5 5.8 14.0 Tallow Fatty Acids (TFA) None0 11.3 8.0 Tallow Fatty Acids EBS 5 10.0 8.5 Tallow Fatty Acids CaSt 58.8 11.0 Hard Tallow Fatty Acids (HTFA) None 0 10.0 9.5 Hard TallowFatty Acids EBS 5 9.5 10.0 Hard Tallow Fatty Acids CaSt 5 8.8 12.0

It was surprising to discover that the careful balancing of thecomposition of the fuel (fatty acids or triglycerides, soft orhydrogenated) with the proper selection of additives promotessuppressing and/or improving undesirable properties in order to attainthe required performance characteristics of both formulations and thearticles produced from them.

Thus, in attempting to make a suitable candle material, one mightcombine either hardened tallow or tallow (to get a base fuel that wouldset up into a suitably firm, but somewhat flexible, shape) with eithertallow fatty acids or hard tallow fatty acids (to increase the height ofthe flame) and, notwithstanding, still produce an article that slumps attoo low a temperature, has an insufficient visible flame, burns for tooshort a time, and/or takes too long to harden in the mold.

Proper application of the EBS additive caused rapid crystallization ofthe candle-type formulation in the mold and provided superior strengthand stiffness of the produced article even when it was still warm. Asshown in Table 4, CaSt increased the length of time the material burns.

Sodium stearate provided a highly visible, bright flame. It is known inthe art that the addition of sodium stearate to a fuel contributes to abright yellow flame.

TABLE 4 Effect of Additives and Fuel Compositions on Properties ofCandle-type Formulations Flame Burn EBS, CaSt, NaSt, Softening height,time, Fuel 1, % Fuel 2, % % % % Point, ° F. cm min. HT, 50 TFA, 50 0 0 0128 1.3 4.0 HT, 35 TFA, 54 5 5 1 149 2.0 4.5 HT, 44 TFA, 45 5 5 1 1521.3 8.0 HT, 55 TFA, 34 5 5 1 154 1.0 9.0 T, 50 HTFA, 50 0 0 0 135 1.57.0 T, 35 HTFA, 54 5 5 1 170 2.0 6.0 T, 44 HTFA, 45 5 5 1 175 1.3 10.0T, 55 HTFA, 34 5 5 1 178 1.3 11.0

In the case of a composite structure, such as a fire log based on woodchips and fatty fuel mixtures (see Table 5), the combination ofadditives added strength and stiffness, held the structure togetherwhile burning, controlled the length of burn, and provided “quickstrength” during post-production while the crystallization of the fuelmixture into a suitable waxy structure takes place.

Therefore, complex blends of soft and hardened hydrocarbon-free,non-polymeric triglyceride-fatty acids (used as fuels) were found to besuitable for making useful articles, such as fire logs and candles, inthe presence of fatty acid-derived additives, such as metal stearatesand ethylene bisamides. The use of such compositions yielded articleshaving the necessary processing and burn characteristics.

TABLE 5 Effect of Additives and Fuel Compositions on the Characteristicsof Wood-containing Composites Flame Burn Softening height, time, VisibleFuel 1, % Fuel 2, % EBS, % CaSt, % NaSt, % Point, ° F. cm min. Color HT,50 TFA, 50 0 0 0 128 8.8 9.0 Blue HT, 35 TFA, 54 5 5 1 149 8.8 12.5Yellow HT, 44 TFA, 45 5 5 1 152 7.5 13.0 Yellow HT, 55 TFA, 34 5 5 1 1546.3 13.5 Yellow T, 50 HTFA, 50 0 0 0 135 8.8 9.5 Blue T, 35 HTFA, 54 5 51 170 8.8 12.0 Yellow T, 44 HTFA, 45 5 5 1 175 7.5 13.0 Yellow T, 55HTFA, 34 5 5 1 178 7.0 14.0 Yellow

In view of the many changes and modifications that can be made withoutdeparting from principles underlying the invention, reference should bemade to the appended claims for an understanding of the scope of theprotection to be afforded the invention.

1. A composition comprising a blend of: (A) at least one triglyceride;(B) at least one fatty acid; and (C) at least one fatty acid derivative.2. The composition of claim 1 wherein the triglyceride/fatty acid ratiois between 90/10 and 10/90 by weight.
 3. The composition of claim 1wherein the fatty acid derivative(s) is (are) selected from the groupconsisting of metal salts of fatty acids, fatty acid amides, fatty acidbisamides, and mixtures thereof.
 4. The composition of claim 3 whereinfatty acid derivatives are selected from the group consisting of calciumstearate, sodium stearate, N,N′-ethylene bisstearamide, and mixturesthereof.
 5. The composition of claim 1 wherein the content of the fattyacid derivative(s), (C), is from about 3 to about 99 percent by weight,based on the total weight of components (A), (B), and (C).
 6. Thecomposition of claim 1 further comprising at least one additive selectedfrom the group consisting of fillers, extenders, modifiers, binders,flame and article colorants, and perfumes.
 7. An article of manufacturecomprising a composition comprising a blend of: (A) at least onetriglyceride; (B) at least one fatty acid; and (C) at least one fattyacid derivative.
 8. The article of claim 7 wherein the compositionfurther comprises at least one additive selected from the groupconsisting of fillers, extenders, modifiers, binders, flame and articlecolorants, and perfumes.
 9. The article of claim 7 wherein the fattyacid derivative(s) is (are) selected from the group consisting of metalsalts of fatty acids, fatty acid amides, fatty acid bisamides, andmixtures thereof.
 10. The article of claim 9 wherein fatty acidderivatives are selected from the group consisting of calcium stearate,sodium stearate, N,N′-ethylene bisstearamide, and mixtures thereof. 11.The article of claim 7 wherein the content of the fatty acidderivative(s), (C), is from about 3 to about 99 percent by weight, basedon the total weight of components (A), (B), and (C).
 12. The article ofclaim 8 wherein a filler is present, said filler being selected from thegroup consisting of cellulose fiber, cellulose derivatives, wood chips,wood fibers, wood flour, flax, kenaf, sisal, jute, rice hulls, cotton,and hemp.
 13. The article of claim 7 wherein said article is a fireplacelog or fire starter block.
 14. The article of claim 12 wherein saidarticle is a fireplace log or fire starter block.
 15. The article ofclaim 7 wherein said article is a candle.
 16. A method for improving theprocessing and flame-burning characteristics of articles comprising ablend of at least one triglyceride and at least one fatty acid, whereinthe method comprises adding to said blend at least one fatty acidderivative.
 17. The method of claim 16 wherein the fatty acidderivative(s) is (are) selected from the group consisting of metal saltsof fatty acids, fatty acid amides, fatty acid bisamides, and mixturesthereof.
 18. The method of claim 17 wherein fatty acid derivatives areselected from the group consisting of calcium stearate, sodium stearate,N,N′-ethylene bisstearamide, and mixtures thereof.
 19. The method ofclaim 16 wherein the content of the fatty acid derivative(s) is fromabout 3 to about 99 percent by weight, based on the total weight of thetriglyceride(s), the fatty acid(s), and the fatty acid derivative(s).20. The method of claim 16 wherein the blend further comprises at leastone additive selected from the group consisting of fillers, extenders,modifiers, binders, flame and article colorants, and perfumes.